NOAA Magazine || NOAA Home Page 2001 IN REVIEW MARKS WARMER TEMPERATURES, ACTIVE HURRICANE SEASON December 17, 2001 Working from the world's largest statistical weather database, NOAA scientists noted that 2001 is projected to be the second warmest on record for the globe. The scientists also report 2001 saw the fifth most active Atlantic hurricane season, drought in parts of U.S. and record cold in Siberia and western Asia. (Click NOAA's 2001 January - November statewide temperature ranks for larger view.) Global Temperatures U.S. Temperatures Active Hurricane Season Scientists at NOAA's Hurricane Research Division, part of the Atlantic Oceanographic and Meteorological Laboratory in Miami, believe this may be due to a natural ocean cycle called the Atlantic Multidecadal Mode, a North Atlantic and Caribbean sea surface temperature shift between warm and cool phases that lasts 25 to 40 years each. The scientists conducted research that shows warmer sea surface temperatures in the North Atlantic combined with a decrease in vertical wind shear contributed to conditions for more hurricanes over a several-year period. Five or more major hurricanes (winds in excess of 111 mph) occurred in 1995, 1996 and 1999. Prior to 1995, five or more major Atlantic hurricanes had not occurred in one season since 1964. A new record number of hurricanes for November was set in 2001 as Michelle, Noel and Olga all were active in the Atlantic Basin during the month. The contiguous U.S. has not been hit directly by a hurricane now for the past two years, although tropical storms have caused significant damage, as evidenced by Tropical Storm Allison. This storm, the costliest tropical storm on record ($5 billion in damage), caused severe flooding in Texas and Louisiana before moving across the Southeast and up the East Coast. Even though the Atlantic hurricane season was above average for the fourth consecutive year, it appears that there were fewer tornadoes in 2001 than average. Eight very strong to violent tornadoes (winds in excess of 158 mph) occurred between March and August 2001. This was much less than the 1950-2000 average of 38. Throughout the past 50 years, there has been little observed trend in very strong to violent tornado activity. U.S. Drought, Floods and
Wildfires The Great Lakes and Northern Great Plains states experienced wetter than normal conditions. Precipitation across the Great Lakes and northern Great Plains states was abundant with flooding along the Mississippi River in April, while Tropical Storms Allison and Barry caused significant flooding along the Gulf Coast states, ending drought conditions in this region. The wildfire season in the U.S. began later than usual, but escalated rapidly. The level of activity for the season was similar to the 10-year average (1990-1999), although Florida, Nevada, Washington and Oregon had more active seasons than is typical. Dry conditions contributed to the increased wildfire activity in these states. This near-average season follows the worst fire season in more than 50 years last year in the southern and western regions of the country. Almost 3.5 million acres have burned during the 2001 season. Global Satellite Data Additional Global Data Drought conditions continued across portions of Pakistan, Afghanistan, India and Iran as the region has suffered from an extreme lack of precipitation for more than three years. In Afghanistan, the drought is perhaps the worst in 30 years. Much of Siberia and western Asia experienced their harshest winter in decades. Temperatures ranged from -60 F (-51 C) to as low as -94 F (-70 C) during January and February. Heavy snows in South Korea were the worst in 20 years. Climate data describing these and other events are available online. NOAA is dedicated to enhancing economic security and national safety through the prediction and research of weather and climate-related events and providing environmental stewardship of our nation's coastal and marine resources. Relevant Web Sites
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